biotin-protein ligase; biotin apo-protein ligase; includes: biotin-[methylmalonyl-CoA-carboxytransferase] ligase; biotin-[propionyl-CoA-carboxylase [ATP-hydrolyzing]] ligase; holocarboxylase synthetase; HCS; biotin-[methylcrotonoyl-CoA-carboxylase] ligase; biotin-[acetyl-CoA-carboxylase] ligase (HLCS)

Function

• post-translational modification of specific proteins by attachment of biotin
• biotinylates CoA carboxylases, including:
  • acetyl CoA carboxylase
  • propionyl CoA carboxylase
  • methylmalonyl CoA carboxylase
  • methylcrotonoyl CoA carboxylase

ATP + biotin + apo-[methylmalonyl-CoA:pyruvate carboxytransferase] = AMP + diphosphate + [methylmalonyl-CoA:pyruvate carboxytransferase]

ATP + biotin + apo-[propionyl-CoA:carbon-dioxide ligase (ADP-forming)] = AMP + diphosphate + [propionyl-CoA:carbon-dioxide ligase (ADP-forming)]

ATP + biotin + apo-[3-methylcrotonoyl-CoA:carbon-dioxide ligase (ADP-forming)] = AMP + diphosphate + [3-methylcrotonoyl-CoA: carbon-dioxide ligase (ADP-forming)]

ATP + biotin + apo-[acetyl-CoA:carbon-dioxide ligase (ADP-forming)] = AMP + diphosphate + [acetyl-CoA:carbon-dioxide ligase (ADP-forming)]

Kinetic parameters:

• KM=224 nM for biotin
• Vmax=143.9 pmol/min/mg enzyme

Structure

• monomer
• belongs to the biotin-protein ligase family

Compartment

cytoplasm, mitochondria

Expression

• mostly expressed in muscle, placenta
• lesser expression in brain, kidney, pancreas, liver & lung

Pathology

• defects in HLCS are associated with holocarboxylase synthetase deficiency

More general terms

• ligase or synthetase
• phosphoprotein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=3141
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:3141
• OMIM: https://mirror.omim.org/entry/253270
• OMIM: https://mirror.omim.org/entry/609018
• UniProt: http://www.uniprot.org/uniprot/P50747.html